export declare function class2color(classes2colors: Record<string, string>, cls: string, colors: string[], numClasses: number): string;
export declare function class2darkenColor(color: string): string;
export declare function unitaryVector(source: any, target: any, newLength?: number): {
    x: number;
    y: number;
};
export declare function unitaryNormalVector(source: any, target: any, newLength?: number): {
    x: number;
    y: number;
};
export declare function rotate(center: {
    x: number;
    y: number;
}, point: {
    x: number;
    y: number;
}, angle: number): {
    x: number;
    y: number;
};